Area Forecast Discussion
Issued by NWS North Platte, NE
Issued by NWS North Platte, NE
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105 FXUS63 KLBF 281149 AFDLBF Area Forecast Discussion National Weather Service North Platte NE 649 AM CDT Sun Apr 28 2024 .KEY MESSAGES... - Chances of showers stick around across western and north central Nebraska today, as a low pressure system brings wrap around precipitation. - A brief break from rain on Monday, with temperatures returning to seasonal and remaining near seasonal through the week. - Chances of precipitation remain almost every day starting Tuesday through the weekend, with the best chances appearing to be Wednesday night into Thursday. && .SYNOPSIS... Issued at 348 AM CDT Sun Apr 28 2024 Upper air analysis and satellite imagery show a upper level trough across the the Desert Southwest, with the trough axis extending roughly from western Nebraska to central New Mexico. The upper level low is over southwest Nebraska and northeast Colorado. At the surface, a low pressure system is noted over south central Kansas, with a stationary front extending northeast to Wisconsin, and a stationary front extending back to a low pressure system in north central Oklahoma. This system has been producing a long line of thunderstorms from southwest Texas through northern Illinois. On the north side of the low, a line of showers is observed over north central Nebraska. && .SHORT TERM /THROUGH MONDAY NIGHT/... Issued at 348 AM CDT Sun Apr 28 2024 The low pressure system begins to trek northeastward today, following the upper level low. As the low track northeastward, it will continue to provide forcing for rain showers across north central Nebraska, with wrap around precipitation across western Nebraska. Of note for this morning, as temperatures remain slightly above freezing this morning, there will be some potential to see show mixing in with the showers. However, given both air and soil temperatures, do not expect any accumulations at this time. Otherwise, today remains a mostly cool and dreary day with overcast skies. By the evening, clouds and showers start moving out of the area from the west to the east, finally pushing out by Monday afternoon. Overnight temperatures drop into the low 30s where skies are clear, with mid to upper 30s under the remaining clouds. By Monday morning, a low amplitude ridge begins moving in over western Nebraska, bringing a temporary break from the rain. Temperatures will climb back into the upper 60s across north central Nebraska, with temperatures in the 70s across western and southwest Nebraska. Temperatures remain relatively mild overnight, with lows in the 40s Monday night. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Issued at 348 AM CDT Sun Apr 28 2024 As the low amplitude ridge treks eastward, a fairly progressive upper level pattern is expected through the week. This brings at least chances of precipitation pretty much every day this week. With this upper level pattern, temperatures should also remain around seasonal though the week. A shortwave sets up over Wyoming on Tuesday, and most model guidance tracks a cold front through the region on Tuesday. This brings another chance for rain this week, particularly across northern Nebraska. Ensembles are not exactly bullish on the rain chances for our area, with the ECMWF ensemble being the most aggressive with around 30-40% chances of rain greater than one tenth of an inch. Even though models are in agreement on a cold frontal passage, temperatures remain mostly in the 60s and 70s on Tuesday. For what it`s worth, the latest SPC convective outlook places a Marginal risk for severe weather to the east of our area, in eastern Nebraska. Though the risk for severe weather appears low at this time, it may be worth keeping an eye on. Wednesday brings around a 30-40% chance of precipitation, however, ensembles are not too enthusiastic about the amounts. Staying with the percentages of at least one tenth of an inch, the ECMWF ensemble again remains the most aggressive, around 20-40% across the region, while the GEFS only getting areas of 10-20% chances. Deterministic models also show a bit of drying in the upper levels behind the Tuesday cold front, which may be impacting precipitation chances Wednesday afternoon. Wednesday night into Thursday morning brings a much better chance of precipitation. A somewhat deeper shortwave is expected to track across Wyoming, with a respectable area of positive vorticity advection aloft. Guidance also suggests a shot of moisture advection in the lower levels. The ensemble guidance seems to be picking up on the synoptic forcing, as probabilities of greater than one tenth of an inch of precipitation are generally 70-80% in this timeframe. Friday into the weekend also keeps chances of precipitation around, however some spread begins to appear in the ensemble guidance, ranging from around a 10-40% chance of measurable precipitation. The upper pattern is expected to remain active, with numerous shortwaves expected, so there should be some level of forcing aloft. Will certainly be worth keeping an eye on, as this week and weekend has the potential to be quite wet across the region. && .AVIATION /12Z TAFS THROUGH 12Z MONDAY/... Issued at 645 AM CDT Sun Apr 28 2024 Widespread rain will continue to pivot across the area as a surface low progresses south to north through the day. Low CIGs and precipitation will likely lead to areas of IFR and even LIFR categories at both North Platte and Valentine terminals. Low stratus will linger through the period at VTN but should break with a return to VFR for at least a brief period at LBF. After improvement during the daytime Sunday at VTN, conditions will again degrade as wrap-around stratus and precipitation chances look to impact the terminal through the end of the period. Some short-term guidance hints at fog development at LBF, but confidence is too low to mention at this time so trends will be monitored. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Richie SHORT TERM...Richie LONG TERM...Richie AVIATION...NMJ